Effect of Pre-Treatment with Sodium Chloride/Sulfuric Acid on the Bornite Concentrate Leaching in Chloride Medium

Abstract

In this work, the effect of the pre-treatment of bornite concentrate with a sodium chloride–sulfuric acid mixture prior to leaching with chloride solutions was evaluated. The influence of the dosage of NaCl and the resting time in the copper solution was evaluated. The solid residues of the pre-treatment were characterized by XRD to evaluate the changes that took place in the bornite. The experimental results show that as the sitting time and the amount of sodium chloride added are increased, the dissolution of the sulfide species also increased. The pre-treatment affects Cu preferentially because it has greater mobility than iron in the bornite crystal lattice. The pre-treatment promotes the formation of soluble Cu and Fe species. The efficiency of the pre-treatment depends largely on the formation of hydrochloric acid in the mixture at the particle level, due to the ease with which it diffuses through the bornite particles, achieving greater penetration of the pre-treatment.

Effect of a pre-treatment with hydrochloric acid on the copper solubilization of a bornite concentrate with posterior leaching in chloride medium

“…Technical grade hydrochloric acid (37.0% pure) was used to the pre-treatment of the concentrate. To simulate the use of seawater and to compare with previous work [21], NaCl (99.9% pure) and H2SO4 (98.0% pure) were used to prepare the leaching solution. Water was deionized before use.…”

“…On the other hand, bornite of samples pre-treated with 15% HCl was completely transformed into idaite during pretreatment, therefore, in the leaching stage, sulfide present in idaite could have been oxidized by Fe(III) and Cu(II), which both get reduced, as proposed in eq. ( 16)- (21).…”

“…The addition of Fe(III) during the leaching stage of bornite is not necessary, as demonstrated by Navarro et al [21] since the same ore carries soluble iron species. When Fe(II) is in solution, it can be oxidized to Fe(III) by the oxygen present in the medium [9].…”

“…In the chalcopyrite leaching field, historically some authors have applied pre-treatments to sulfide copper ores before the leaching, where the pre-treatment with H 2SO4 and NaCl had reported promising results [17][18][19][20][21]. Pre-treatment is a necessary step to improve the leaching of copper oxide and secondary sulfide ores.…”

Bacterias gram negativas, resistentes al cloro y degradantes de gasolina y diésel, aisladas de aguas subterráneas y costeras

“…La actividad oxidante del cloro, caracterizado como un poderoso germicida, afecta la integridad de la membrana y ocluye su permeabilidad, asimismo, interfiere en la síntesis de las proteínas al reacionar inespecíficamente con el grupo amino de los péptidos, provocando la muerte de los microorganismos (CONAGUA s.f.). Por otra parte, esa misma resistencia bacteriana ha traído diversos beneficios ambientales, debido a lo relevante de la biorremediación de espacios contaminados con solventes, explosivos, hidrocarburos aromáticos policíclicos, pesticidas, clorofenoles así como hidrocarburos derivados de petróleo (BENAVIDES LÓPEZ DE MESA et al, 2006;BETANCUR CORREDOR, PINO, PEÑUELA, & CARDONA GALLO, 2013;GÓMEZ CAICEDO et al, 2013;NAVARRO, VARGAS, CASTILLO, & SEPÚLVEDA, 2020).…”